Using latest version, just adding a task, about 90% of the time adds them twise.
Wierdest thing is the dupes don't show on web version.
Which version of Android are you running, and please confirm the app version you are using. You say 90% of the time, can you tell the difference, what do you do when it does work, whats the details of the tasks.
Running Android 4.3. Play Store confirms Todoist latest.
Can't think of any other information i could differantiate.. Hope something
Seems that only tasks and projects that were created with the app working offline - are causing dupes.
Hope this helps
We are going to be releasing an update to address issues with adding of tasks offline, I believe this is related.
We hope this will release soon, though do not know of an ETA.